A conventional magnetic bearing amplifier is similar in topology to that used for a switched reluctance drive. However, the magnetic bearing amplifier situation differs in that the power transmitted will be ideally reactive (since no mechanical work is being done).
In practice, the magnet can be modelled as an inductor with copper losses and maybe even core losses. However, in installations with long power cables going to the magnetic bearings (which is often the case in real life implementations, since separation between the machinery containing the bearings and the bearings driver circuitry is often required, e.g. where the bearing is in a volatile gas compressor), the capacitance and transmission line effects of the long magnet power cables going to and from the magnetic bearings and their respective driver circuitry will result in high currents at the switching edges and very high voltages at the load (i.e. at the magnetic bearing).
High currents might cause damage or other detrimental effects to the bearings or driver circuitry. The detrimental effects may also be amplified, which is a particular problem because the operating voltages for such magnetic bearings are (already) typically in the order of several hundred volts (e.g. 600V).
Accordingly, there is a need for an improved magnetic bearing drive system.